The national housing index has registered annual gains of 5 percent or more for 16 months.

David Blitzer, chairman of the index committee at S&P Dow Jones Indices, noted that housing construction is running well below historical levels. "Without more supply, home prices may continue to substantially outpace inflation," he said.

The national index is running 6.1 percent above the peak it reached in July 2006 — before prices went into a 27.4 percent freefall — a collapse that tipped the American economy into the worst recession since the 1930s. The national home-price index hit bottom in February 2012 and has bounced back 46.2 percent since then.

The higher prices and shortage of inventory may be denting sales. And a December cold snap may have kept buyers out of the market. The Commerce Department reported last week that new-home sales skidded 9.3 percent in December. And the National Association of Realtors said sales of existing homes dropped 3.6 percent last month.